Mesenchymal stem cells derived from adipose tissue are pluripotent to differentiate into myocytes, adipocytes or others. They have an immunosuppressive activity. Complex perianal fistula is difficult to cure and easy to relapse. Autologous adipose stem cells have shown efficacy and safety on Crohn's fistula in phase 1 study. Based on these results, the investigators would apply autologous adipose stem cells on complex perianal fistula to evaluate their efficacy and safety.